Lasers have a wide variety of uses, and the number of uses expands as the benefits of lasers are tested in new markets. Such expanded uses often require significant innovation to meet the demands of new uses. Availability of new types of lasers is important in this process. Presently, many new wavelengths of inexpensive laser diodes are now available, and their properties have potential for broadening the use of lasers in industry, medicine and home uses, by opening up applications that require higher power lasers for high volume low cost applications.
To make such projects practical, it is necessary to solve key problems. In particular, higher power requires improvements in numerous areas, including heat dissipation, size, cost, and safety. It is especially important to be careful to minimize costs for laser systems intended for home use and other consumer or non-traditional laser markets. In such markets, there is a need for efficient manufacturing, to obtain costs suitable for mass marketing.
Cost minimization requires not only large volume production of components, but minimization of complexity and associated assembly labor. In particular, rework or manual adjustment of alignment should be avoided. Such problems have been solved for low power semiconductor optical devices, such as LEDs (light emitting diodes) used in reading optical discs and the like. In these systems the semiconductor LEDs need to have certain power levels, but precise optical alignment and focus are not required, because emission is close to the disc, and detection of signal does not require precise focusing. The absence of a requirement for focusing or re-focusing is typical of current large-volume laser chip applications.
However, emerging uses for low cost high power lasers, for example as described in our co-pending application PCT/US2009/001350, published as WO 2009/111010 A1, require precise optical alignment of a laser with an instrument, and in some cases a sharp focus. Yet in consumer uses, the cost of the laser components of a system must be minimized. The production cost of such systems comprises the production of the laser semiconductor chips; the mounting of the chips in a device; and the alignment and testing of the device.